Water dispersible corrosion inhibitor



United States Patent- WATER DISPERSIBLE CORROSION INHIBITOR Loyd W.Jones, Tulsa, Okla., assignor to Pan American Petroleum Corporation, acorporation of Delaware Serial No. 335,161

No Drawing. Application February 4, 1953 13 Claims. '(Cl. 2s2 -s.5's

This invention relates to corrosion inhibitors and more particularly todispersing oily inhibitors in water.

Many of the more effective corrosion inhibitors are of an oily nature;that is, they are soluble in oil and insoluble in water. Examples ofsuch compounds are the imidazoline derivatives sold under the Kontoltrademark, and

the amine complexes with various organic acids described I in myco-pending U. S. patent application No. 288,705 filed May 19, 1952, nowPatent No. 2,756,211. The reaction products of formaldehyde with amines,and the rosin amines and their derivatives are other examples of oilsoluble and water insoluble corrosion inhibitOrs.

Many corrosive systems are predominately aqueous in nature, some of themcontaining no oil at all. Several means have been tested for dispersingthe oily corrosion inhibitors in these systems. One means has consistedof treating the inhibitors with ethylene oxide t oadd polyoxycthylenechains to the inhibitormolecule in order to increase water solubility.This 'method has been fairly successful for dispersing the oilyinhibitors in fresh water but has been incapable of dispersing thesematerials in brines such as those encountered in some-oil fields. Sinceoil field waters are almost always brines, the failure of the ethyleneoxide treated inhibitor to mix readily with brines has been a seriousdefect of such inhibitors.

Theoretically, it should be possible to disperse oily inhibitors inbrines by the use of non-ionic emulsifiers. Many of these materials havebeen found to be highly In view of the foregoing problems anddifiicu'lties, it is" an object of this invention to provide a method oftreating corrosive aqueous systems with an oily corrosion inhibitor.Another object is to provide a method for dispersing an oily inhibitorin brines. An additional object is to provide a corrosion-inhibitingcomposition containing an oily corrosion inhibitor, the compositionbeing of:

such a nature that the inhibitor will disperse in a brine into which thecomposition is mixed. A spec fic ob ect of the invention is to provide acorrosion inhibiting composition containing an oily inhibitor, whichcomposition when diluted by a mixture of oil and brine causes theinhibitor to be dispersed principally in the aqueous phase.

In general, I accomplish the objects of my inventlon by mixing the oilyinhibitor with at least three other materials: an oil, a mutualsolvent'for oil and water, and certain poltyglycol or polyglycerolethers of non-aromatic alcohols employed as dispersing agents. By way ofexample, the composition may'consist of about 50 percent by volume of acorrosion inhibitor such as the octadecylamine salt of fatty acids,about 40 percent by volumeof an oil such as'kerosene, about 5 percentbyvolume ofa mutual solvent, such as ethanol, for oil and water-and;

about 5 percent by volume of a-dispersing agent such as the ether oflauryl alcohol with a polyglycol containing about 20 ether linkages. Tothis mixture, about 2 percent of water may be added to reduce theviscosity and to decrease the turbidity of the composition. It will beobserved that the composition consists of:four essential ingredients andanother which is highly desirable. but optional. dispersing agent,second, an oil, third, a mutual solvent for oil and waterrand fourth,the oilyinhibitor. e.-The, These constituents optional fifth ingredientiswater. will now be considered in more detail.

, DISPERSING AGENT The dispersing agent should belong to thenclass ofwater soluble non-ionic ester-free ethers of an alcohol and a polyglycolor polyglycerol. broad family are not operable, however. the material tobe effective for my purposes, the alcohol,

portion should be non-aromatic since ,alkylated phenols. have been foundto produce dispersing agents ineffective in brines. The alcohol may,however, contain anaromatic ring so long as the hydroxyl group is notattached to it. Preferably, the alcohol should be a straight chainsaturated or unsaturated material such as lauryl oroleyl alcohol. Thealcohol should contain at least twelve carbon atoms to providesufiicient oil solubility in this portion of the molecule.

more than about 20 carbon atoms since a larger number of carbon atomsresults in decreased oil solubility. In"

general, the vthioethers can also be employed,the limits outlined forthealcohols being observed for analogous mercaptans. The polyglycol orpolyglycerol portion of"; the dispersing agent should contain at leastfour ether linkages in order to provide sufficient water solubility;

to cause concentration of the dispersing agent at oil-water interfaces.Dispersing agents prepared with such limitednumbers of ether linkagesare operable to a limited extent but many more ether linkages should bepresent for best Polyglycols are much more generally employed thanpolyglycerols. It is often more convenient to refer results.

to the polyglycol portion of a dispersing agent as a polyoxyethylenechain. Thus, it can be said that the dispersingf agent should contain atleast five oxyethylene groups and preferably at least 10. Normally, notmore than about 30 oxyethylene groups are employed although dispersingagents containing larger members of oxyethylene groups are operable toat least a limited extent. 7

The dispersing agents may be conveniently represented by the formula RXWwherein R is a non-aromatic hydro? carbon radical containing at least 12carbon atoms, X is oxygen or sulfur, and W is a polyglycol orpolyglycerol portion containing at least 4 ether linkages.- The term Rin the formula is intended to be vbroad enough to in--' clude theoperable alcohols and inercaptans described above. Thus, the termnon-aromatic hydrocarbon radical includes radicals which contain anaromatic group so long as this group is not attached t'o'the element Xin the formula. The term W is intended to be broad" enough toincludeoperable forms of the polyglycols (polyoxyethylene chains) andpolyglycerols'described above. i Apreferred class of dispersing agentsma be repre-' sented by the formula R'OW' in which R is a straight chainhydrocarbon radical containing from 12 to 20 carbon atoms, 0 ,is oxygen,and WT is a polyoxyethylenechain containing between about 10 and 30oxyethylene groups. A highlyveffective example of the class ofdisiPatented June 17, 1958 The four essential constituents are: first, a,

All members of'this In order for.

To form the most effective dispersing agent, preferably the alcoholshould contain no" persing agents just'described is the lauryl alcoholether of a polyoxyethylene chain containing about 20 oxyethylene groups.The concentration of the dispersing agent in the water dispersiblecompositions should amount to at least about 2 percent by volume of thecomposition if effective dispersion is to be obtained. An upper limit ofabout percent by volume is normally observed for economic reasons, butpercent has been employed with good results. The dispersing agent isnormally employed in a concentration of about 4 to 6 percent by volumeof the corrosion-inhibiting composition.

OIL

In general, most petroleum oils may be employed with at least fairresults. It is highly preferred, however, to employ a refined petroleumfraction such as kerosene or refined mineral oil. The principaladvantage of using such a refined product is to avoid the effects ofimpurities in crude oils. A particularly desirable class of oils is theclass of distilled petroleum products since the distillation operationnormally eliminates impurities which may cause difficulties. Of thisclass of distilled petroleum fractions, those having higher viscositiesand lower flash points have been found to be most desirable since theyeliminate fire hazards and seem to disperse more readily in water. Aconvenient test for the preferred group of distilled petroleum fractionsis ASTM test D86-46 which describes the standard method for distillationanalysis of petroleum fractions. The most desirable groups of oils arethe distilled petroleum fractions having a 10 percent boiling 0 on thesurface of metal to be protected. The other function is a dilutingaction which is apparently essential to obtain effective dispersion ofthe inhibitor in the aqueous phase of the system to be protected.

The oil should be present in the composition in an amount equal to atleast about 10 percent by volume of the composition. This amount of oilseems to be sufficient to cooperate with the inhibitor in formingeffective films. The oil in these concentrations also producessatisfactory dispersions of oily inhibitors in the aqueous system. It isnormally preferred to use about to percent by volume of oil since thisamount is more than adequate for coating purposes and gives very gooddispersions of inhibitor, but at the same time avoids excessive volumesof the inhibiting composition which would result from the use of largerpercentages of oil. Generally, an upper limitation of about 80 percentby volume of oil should not be exceeded for satisfactory operation.

It has been found that aromatic hydrocarbons such as benzene, tolueneand xylene can serve as the oil portion of the inhibitor composition.Such materials also seem to fulfill the requirements of a mutual solventfor oil, inhibitor and dispersing agent. Thus, by using aromatichydrocarbons, the mutual solvent can be omitted and op erabledispersions still can be obtained with or without water as a constituentof the composition. Better and more stable dispersions arev obtained,however, if a mutual solvent such as methanol is also employed.

MUTUAL SOLVENT The real problem in selecting a mutual solvent is to findone which is a solvent for both the oil and the dispersing agent. It hasbeen found, however, that a simpler rule to follow is to select a mutualsolvent for oil and water. The dispersing agent, being highly watersoluble, is also soluble in these mutual solvents for water and oil.Preferably, the mutual solvent should be miscible in all proportions, ornearly so, with both oil and water. Suitable mutual solvents includematerials, such as ethers, ketones, esters and alcohols. As specificexamples of the aforesaid classes of mutual solvents, there may bementioned acetone, methyl acetate, p-dioxane, the 2alkoxyethanols soldunder the trademark Cellosolves, and the lower molecular weight alcoholssuch as methanol, ethanol and isopropyl alcohol, said alcoholsrepresenting the preferred class of mutual solvents which may beemployed in carrying out my invention. In this connection, l-butanol hasbeen successfully employed but is not sufficiently water soluble toproduce dispersions as stable as those formed by use of the alcoholshaving three or less carbon atoms per molecule. The mutual solventperforms several functions. First, it aids in forming a homogeneousmixture of the water soluble dispersing agent, the oil and the oilyinhibitor. Second, it aids in the dispersion of the inhibitor into thewater contacting the surface to be protected. In this regard, itsfunction is similar, apparently, to the diluting action of the oilpreviously referred to. Third, the mutual solvent reduces the viscosity,gel strength and pour point of the corrosion inhibiting composition,thus facilitating handling of this composition. Methanol is a preferredmutual solvent which is easily obtained in almost anhydrous conditions.

The mutual solvent should be employed in an amount of at least about 2percent by volume of the composition in order to obtain an appreciableeffect. As much as 20 percent of the mutual solvent has been employedwithout ill effects. However, this large quantity of solvent increasesthe cost and the volume of the composition to such an extent that anupper limit of 10 percent is generally observed. Mutual solvents arenormally employed in a concentration of about 4 to 6 percent by volumeof the composition.

INHIBITOR The inhibitor may be any of the oily corrosion inhibitorsknown in the art. Several of these materials have been previouslymentioned. Others will occur to those skilled in this art. A preferredclass of inhibitors is the class of amine complexes with organic acids,described in my co-pending U. S. patent application 288,705, referred toabove. A particularly desirable amine-acid complex for use in my waterdispersible composition is the complex derived from Armour and CompanysDuomeen T and Alox Corporations 425 acids. Duomeen T has the formulaR"NH(CH NH wherein R" is a straight chain hydrocarbon radical containing16 to 18 carbon atoms. The Alox 425 acids are produced from a normallyliquid fraction of petroleum by liquid-phase partial oxidation of thelatter. Another highly desirable amine acid complex is formed betweenDuomeen T and VRl acids obtainable from Rohm and Haas. The VR-l acidsare polybasic acids obtained as a by-product from the caustic fusion ofcastor oil. They have an average molecular weight of about 1000 and anaverage of about 2 carboxylic acid groups per molecule. They areconveniently described as the non-volatile residue, containinglong-chained carboxylic acids, remaining from the vacuum distillation ofby-product acids obtained in the preparation of sebacic acid from castoroil by treatment with alkali. These VR-l acids are described in moredetail in U. S. Patents 2,267,269 issued to Cheetham et al., and2,471,230 issued to McKeever.

The inhibitor normally is employed in the water dispersible compositionin a concentration of about 50 percent by volume. However, it can beemployed in concentrations as high as percent, or'it can be diluted witheither the oil or mutual solvent to a much lower concentration, possiblyas low as about 10 percent, but preferably no lower than 30 percent. Aconcentration between 35 and 65 percent by volume is suggested as themost desirable range.

WATER As previously noted, the water-dispersible composition is operableif it includes no water. Therefore, the lower limit of water content ofthe composition is zero. An upper limitation of about 3 percent watershould be ob- APPLICATION OF COMPOSITION The principal application of mywater-dispersible composition is to oil wells producing a'substantialamount of' water; that is, about 10 percent or more of the totalproduction. The undiluted composition may be introduced into the annularspace between the tubing and casing or through the tubing in a containerwith an orifice. It may also be introduced in undiluted form'in a slowlysoluble stick or pellet. It is preferred,'however, to'dilute thecomposition with water before introducing it into a well. The results ofsuch dilutions are that the'inhibitor reaches the bottom of the wellmuch morexquickly with less hold up, and. more elfectively-coversexposed metal surfaces on the way down. Dilution also aids passage ofthe inhibitor through oil layers since if the inhibitor is dispersed ina continuous waterphase, excessive dispersion of the oil solubleinhibitor in long oil columns is prevented. If the inhibitor is dilutedbefore introduction into the well, it reaches. thebottom of the well andstarts up the tubing at aconcentration much closer to the desiredequilibrium concentration of inhibitor in the system to be treated. .Bysuch dilution, a larger volume is provided in case it is desired tointroduce the inhibitor into the well over a longer period of time. Theusual practice, however, is to introduce, in a batch, suflicientinhibitor to last for a period of a day or more.

If the water in the production from the well amounts to at least about50 percent of the total production, the inihibitor can be mixed'into theoil and water to avoid bringing water to the well from tanks orseparators at some distance from the well. If the inhibitor is to bemixed into the total production, a simple procedure is to introduce thecomposition into a pot into which the well production enters. at atangent. The resulting swirling action is usually quite adequatetodisperse the inhibitor in the aqueous phase. In normal practice,=aboutone volume of inhibitor composition ismixed-with about to ,10 volumes ofproduction. hibitor is then washed down the annular space with abo t toor more volumes of production. This batch of materials apparently mixesinto the liquids in the bottom of the well and is produced by the wellat a fairlyi-slow rate over a period of time, generally'a'boutequaltothe period between treatments. In diluting the composition beforeuse, an amount of water should. be employed at least equal to the volumeof inhibiting. composition: If less water is employed, a thick. viscousemulsion-with considerable gel strength results, which is ratherdifficult tohandle. 7 e

If the inhibiting composition is tobe -appliedrto surface systems suchas water-disposal or water=flooding distribution systems, di luti'on isagain advisable to obtain. efiective treatment near. the point ofinjection by having a good dispersion in water when introduced into thesys: tem. Thecomposition maybe introduced. in a singlev batch, but insurface equipment, it may be advisable to v meter the liquid in almostcontinuously. .A convenient means of introduction .is to metertheinhibitor into the.

intake of a pump handling the water inthe system; The,

inhibitor may be introduced downstream from the pump, however, duetof'its -ready.:dispersibility in water. j I

Sutficient of the inhibiting composition isnormally em. ployed toprovide an inhibitingconcentration, in mildly corrosive systems of 1.0to,'20 p. p,, m by weight'ba's ed; on the total liquids in the system tobe. treated; that is,

The entire batchof diluted intion should be based on the, amount of bothoil and.

water; 'If batch injection is employed ev'e'ry day, the totaldailyfamount of liquids should be employed as a basis for calculatingthe amount of'inhibitor to'be used. A

concentration of 100 to 200 p. p. m. is considered high for normaltreatments. If a pretreatment is used to establish protection .quickly,concentrations as high as 50 tion of the following examples. 7

Example I A four-component composition was prepared as follows:

Percent by volume Material:

Inhibitor 6O Dispersing agent 5 Kerosene i 30 Methanol 5 The inhibitorwas the octadecyl amine-acid complex obtained by reacting the amine withacids derived by the liquid phase partial oxidation of a liquidpetroleum fractiori. The dispersing agent was an ether of lauryl alcoholr and a polyoxyethylene chain containing about 23 'oxyethylene groups.

solution .at atemperature of F. One part of this mixture was added to 9parts of an aqueous solution con- The composition was a slightly turbidtaining about 9 percent by weight of sodium chloride and 1. percent byweight of calcium chloride.

had separated from the water phase. Part of the small amount of kerosenepresent also remained dispersed in the aqueous phase. V

' Example II Type of Agent 7 7 Stability of Dispersion Dispersing AgentEther of a i alcohol Brij 35 Dispersion stable after 72 and apolyglycol. hours. Antara 210 LA-. do.. Do. Antarox D Ether of oleylalcohol Dispersion stable after 24 and a polyglycol; hours. 7 a TritonX-100.- Ether of alkylated phe- D isperslonbrokerapidly. 1101 and apolyglycol. Antarox 2 9404;; .do Do. a Myrj 53 Ester of stearic acid andFair dispersion but broke;

a polyglycol. .in about' 10 minutes.

Tween 205.; Ester of lauric acid and Good dispersion but broke in aboutminutes.

polyoxyethylene sor bitan.

SO .far as is'known all'the dispersing agents listed contain about 20.oxyethylene groups'per molecule except Antarox A-404 which containsabout 30 of these groups.

Itwill be noted that the polyglycol ethers of non-;

aromatic alcohols are-all highly desirable dispersing agents, butthatpolyglycol ethers -oflalkylated phenolsf are not operable.- fordispersing oily inhibitors inbrines.

if thc sy atains both 9.1 some. t sgcqnsent a-s fi' 'l y' highly ctiveuif eshzwatcr but the ai p ra The. mixture V with the salt water wasshaken by hand 50 times and the stability observed. Most ofthe inhibitorwas .still stably dispersed after 24 hours, but part'of the kerosenesion fails when salt is added. The ester-type dispersing agents formdispersions which are sometimes very good except that they are toounstable in brines to permit use in most commercial applications.

Example III A composition was prepared as described in Example I exceptthat the inhibitor was Kontol 118, a solution of an imidazolinederivative in kerosene more fully described in U. S. Reissue Patent23,227 Blair et a1. Since the Kontol 118 already contained kerosene, noadditional kerosene was added, the composition consisting of 90 percentby volume of Kontol 118 (combined inhibitor and kerosene) and percent byvolume each of the dispersing agent and methanol. When one part byvolume of this composition was mixed with 9 parts by volume of the brinedescribed in Example I, a good dispersion resulted which was stillstable after 24 hours.

Example IV V Compositions were prepared as described in Example I exceptthat various mutual solvents were employed. The resulting compositionsand the types of dispersions formed when mixed with brine as describedin Example I are tabulated in Table II.

TABLE II Mutual Solvent Nature of Concentrate Nature of DispersionEthanol Non-viscous but slight- Stable after 24 hours.

1y turbid. l-Butanol Clear non-viscous solu- Dispersion not complete,tion becoming turbid but stable for about an when cooled to about hour.80 F. Acetone Opaque and thick Fair dispersion stable for several hours.Z-Butoxyethanol Olear non-viscous solu- Fairly good dispersion (BlutplCellotion. stable for several hours. so ve Example V Example VI Waterwas added to the corrosion-inhibiting compositions describedin ExamplesI through V inclusive. In every case, the amount of water was about 2percent by volume of the resulting composition. In every instance theresults were a decrease in viscosity and in turbidity of thecompositions. The presence of water also seemed to produce animprovement in the dispersion in brine obtained when mutual solventssuch as acetone and l-butanol were employed.

When 3 percent water was added to the composition described in ExampleI, a slight increase in viscosity and a return of a slight turbidityoccurred as if the solution, or water-'in-oiltype emulsion, was about tobecome an oil-in-water type of dispersion. Use of 5 percent Waterdefinitely caused the formation of a thick emulsion paste. When anamount of water was employed equal to the amount or the compositiondescribed in Example I, the

the composition in the water phase. 7

Example VII -A three-component composition was'prepared consisting ofabout 60 percent by volume of the inhibitor. and 5 percent by volume ofthe dispersing agent described in Example I, together with about 35percent by volume of benzene. The aromatic hydrocarbon apparentlyperformed the dual function of the oil and of the mutual solvent sincethe resulting composition was quite similar to those prepared withkerosene and an alcohol except that the dispersion of the inhibitorinsalt water was not quite as complete or as stable as when kerosene andalcohol were employed. The composition was still satisfactory forcommercial use, however.

Example VIII To the four-component composition described'in Example I, 2percent. byvolume of water was added to form an inhibitor concentratesuitable for testing the dispersibility ofithe inhibitor in brine in thepresence of crude oil.v One part of the concentrate was added to 2 /2parts of crude oil from the Anton-Irish Field in Texas and 2 /2 parts ofa brine containing 10 percent sodium chloride by weight. The mixture wasshaken thoroughly and allowed to stand. The oil separated in a fewseconds leaving a brown opaque aqueous phase which appeared to beidentical to the dispersions of inhibitor prepared in the absence ofcrude oil. Further tests with the aqueous dispersions prepared with andwithout crude oil included evaporating samples of the dispersions todryness and analyzing by means of the infrared spectrograph. The

Example IX To test the corrosion inhibiting ability of thewaterdispersible composition, a five-component composition was prepared,containing the materials in the quantities indicated in Table III. Thecorrosion inhibitor was the complex of Duomeen T with VR-1 acids. Thecomplex contained approximately equal parts by Weight of the amine andacid components.

TABLE III Material: Amount, percent by volume Corrosion inhibitor 50Kerosene 38 Brij 35 5 Methanol 5 Water 2 Total This composition wasmixed into 800 ml. of an aqueous sodium chloride brine containing 5percent by weight of the salt, and 16 ml. of kerosene in a one-literbottle. The final concentration of the corrosion inhibitor'in themixture was 200 parts per million by weight. A tared polished mild steeltest panel 1" x 1" x' was suspended in the brine by a metal rod fromwhich the panel was insulated by plastic washers. The bottle wasstoppered, but provision was made for a corrosive gas stream containing98 percent air and 2 percent hydrogen sulfide to bubble through theliquids in the bottle. The gas stream was, bubbled at a rate of /2 cubicfoot per hour through the bottle in series with a duplicate and twoduplicate controls lacking the inhibiting composition; The bottles werevigorously shaken for 15 consecutive minutes every two hours. Afterseven days exposure under these conditions at 100 .F. the panels wereremoved'from 9v the bottles, dipped in dilute inhibited hydrochloricacid solution, rub-bed lightly to remove adhering scale when necessary,rinsed in distilled water, dried and weighed. The two control panelslost 0.7109 and 0.6607 grams, an average of 0.6858. The two inhibitedpanels lost 0.0058 and 0.0045 grams, an average of 0.0052 gram. Thus,the inhibition was a little more than 99.2 percent, no pitting or localattack being visible. It is apparent from this test that the inhibitorremains highly effective when dispersed in the aqueous phase.

From the above description and examples, it will be observed that I haveprovided a method and composition for dispersing an oily corrosioninhibitor in an aqueous phase even when the aqueous phase is a brine andeven when crude oil is present in an amount equal to the volume of theaqueous phase.

I claim:

1. A brine-dispersible corrosion-inhibiting composition comprising fromabout 10 to 80 percent by volume of an oil-soluble, water-insolublecorrosion inhibitor, from about 10 to 80 percent by volume of adistilled petroleum fraction, from about 2 to 10 percent by volume of amutual solvent for water and the distilled petroleum fraction, and fromabout 2 to 10 per cent by volume of a dispersing agent having theformula ROW, wherein R is a non-aromatic hydrocarbon radical containingat least 12 carbon atoms, is oxygen and W is a polyglycol containing atleast 4 ether linkages.

2. A brine-dispersible corrosion-inhibiting composition comprising fromabout to 80 percent by volume of a liquid, oil-soluble, water-insolublecorrosion inhibitor, from about 10 to 80 percent by volume of adistilled petroleum fraction, from about 2 to 10 percent by volume of amutual solvent for water and said petroleum fraction,

from about 2 to 10 percent by volume of a dispersing agent having theformula R'OW' wherein R is a straightchain hydrocarbon radicalcontaining from 12 to carbon atoms, 0 is oxygen, and W is apolyoxyethylene chain containing between about 1'0 and oxyethylenegroups, and from 0 to about 3 per-cent by volume of water.

3. A brine dispersible corrosion-inhibiting composition comprising fromabout 10 to 80 percent by volume of a corrosion inhibitor consisting ofapproximately equal parts by weight of an amine and an organic acid,said amine containing at least 12 carbon atoms per molecule and saidacid containing at least 10 carbon atoms per molecule; about 10 to 80percent-by volume of a distilled petroleum fraction having as A. S. T.M. 10 percent boiling point of at least about 400 F.; from about 2 to 10percent by volume of an alcohol containing no more than three carbonatoms per molecule; from about 2 to 10 percent by volume of a dispersingagent having the formula ROW wherein R is a straight-chain hydrocarbonradical containing from 12 to 20 carbon atoms, 0 is oxygen, and W is apolyoxyethylene chain containing between about 10 to 30 oxyethylenegroups; and from 0 to about 3 percent by volume of water.

4. A brine-dispersible corrosion-inhibiting composition comprising fromabout to 65 percent by volume of a corrosion inhibitor consisting ofapproximately equal parts by weight of an amine and an organic acid,said amine having the formula R"NH('OH NH wherein R" is a straight-chainhydrocarbon radical containing 16 to 18 carbon atoms, and said acid isproduced from a normally liquid fraction of petroleum by liquid phasepartial oxidation of the latter; from about 30 to 60 percent by volumeof kerosene; from about 4 to 6 percent by volume of methanol; from about4 to 6 percent by volume of the polyoxethylene ether of lauryl alcoholwherein the polyoxyethylene portion contains from about 15 to about 25oxyethylene groups; and from 0 to about 2 percent by volume of water.

5. A brine-dispersible corrosion-inhibiting composition comprising fromabout 35 to '65 percent by-volume offa corrosion inhibitor? consistingof approximately equal parts by weight of an amine and an acid, saidamine 'having the formula R"N'H(OH NH wherein R" is a straight-chainhydrocarbon radical containing 16 to'18 atoms, and said acid is thenonvolatile residue, containing long-chained carboxylic acids, remainingfrom the vacuum distillation of by-product acids obtained in the preparation of se'bacic acid from castor oil 'by treatment with alkali; fromabout 30 to 60 percent by volume of kero- 1 carbon liquid and from about2 toIO percen-t by volume I of a dispersing agent having the formulaROW, wherein R is a non-aromatic hydrocarbon radical containing at least12 carbon atoms, 0 is oxygen and W is a polyglycol containingat least 4etherlink-ages.

7. A brine-jdispersible corrosion-inhibiting composition comprising fromabout 10 to percent by volume of a liquid oil-soluble, water-insolublecorrosion inhibitor, from about 10 to about 80 percent by volume of anaromatic hydrocarbon liquid, frorna-b'out 2 to 10 percent by volume of adispersing agent having the formula ROW' wherein R is aVstraight-chainhydrocarbon radical containing from about '12 to 20 carbon atoms, 0 isoxygen, and W is a polyoxyethylene chain containing between about 10 and3-0 oxyethylene groups, and from 0 to about 3 percent by volume ofwater.

8. A brine-dispersible corrosion-inhibiting composition comprising fromabout 1-0 to 80 percent by volume of a corrosion inhibitor consisting ofapproximately equal parts by weight of an amine and an organic acid,said amine containing at least 12 carbon atoms per molecule and saidacid containing at least 10 carbon atoms per molecule; about 10 to 80percent by volume of an aromatic hydrocarbon liquid, from about 2 to 10percent by wherein R is a straight-chain hydrocarbon radical containingfrom 12 to 20 carbon atoms, 0 is oxygen, and W is a polyethylene chaincontaining between about 10 and 30 oxyethylene groups; and from 0 toabout 3 percent by volume of Water.

9. A method of inhibiting corrosion in a well producing liquidscontaining a substantial percentage of water comprising introducing intosaid well a brine-dispersible corrosion-inhibiting compositioncomprising from about 10 to 80 percent by volume of a liquid,oil-soluble, waterinsoluble corrosion inhibitor, from about 10 to 80percent by volume of a distilled petroleum fraction, from about 2 to 10percent by volume of a mutual solvent for water and said petroleumfraction, from about 2 to 10 percent by volume of a dispersing agenthaving the formula ROW' wherein R is astraight-chain hydrocarbon radicalcontaining from 12 to 20 carbon atoms, 0 is oxygen, and W is apolyoxyethylene chain containing between about 10 to 30 oxyethylenegroups, and from about 0 to about 3 percent by volume of water.

10. A method of inhibiting corrosion in a well producing liquidscontaining a substantial percentage ofwater comprising introducing intosaid well a brinedispersible corrosion-inhibiting composition comprisingfrom about 10 to 80 percent by volume of a liquid oilsoluble,water-insoluble corrosion inhibitor, from about 10 to about 80 percentby volume of an aromatic hydrocarbon liquid, from about 2 to 10 percentby volume of a dispersing agent having the formula R'OW' wherein R isastraight-chain hydrocarbon radical containing inhibitor, from 11 from 12to 20 carbon atoms, is oxygen, and W is a polyoxyethylene chaincontaining between about and 30 oxyethylene groups, and from 0 to about3 percent by volume of water.

11. A method of inhibiting corrosion in a Well producing liquidscontaining a substantial percentage of brine comprising mixing one partby volume of a brine-dispersible corrosion inhibiting composition withat least one part by volume of said brine, and introducing the mixtureinto said well, said corrosion-inhibiting composition comprising fromabout 10 to 80 percent by volume of a liquid, oil-soluble,Water-insoluble corrosion inhibitor, from about 10 to 80 percent byvolume of a distilled petroleum fraction, from about 2 to 10 percent byvolume of a mutual solvent for water and said petroleum fraction, fromabout 2 to 10 percent by volume of a dispersing agent having the formulaR'OW wherein R is a straightchain hydrocarbon radical containing from 12to 20 carbon atoms, 0 is oxygen, and W is a polyoxyethylene chaincontaining between about 10 and 30 oxyethylene groups, and from 0 toabout 3 percent by volume of water.

12. A method of inhibiting corrosion in a well producing liquidscontaining a substantial percentage of brine comprising mixing one partby volume of a brinedispersiblc corrosion inhibiting composition with atleast one part by volume of said brine, and introducing the mixture intosaid well, said corrosion-inhibiting composition comprising from about10 to 80 percent by volume of a liquid oil-soluble, water-insolublecorrosion inhibitor, from about 10 to about 80 percent by volume of anaromatic hydrocarbon liquid, from about 2 to 10 percent by volume of adispersing agent having the for- 12 mula R'OW wherein R is astraight-chain hydrocarbon radical containing from 12 to 20 carbonatoms, 0 is oxygen, and W is a polyoxyethylene chain containing betweenabout 10 and oxyethylene groups, and from 0 to about 3 percent by volumeof water.

13. A method of inhibiting corrosion in a well producing a substantialpercentage of both brine and oil in the liquids produced comprisingmixing one part by volume of a brine-dispersible corrosion inhibitingcomposition with sufiicient of the liquids produced by said well toprovide at least one part by volume of brine, and introducing themixtureinto said well, said corrosioninhibiting composition comprisingfrom about 10 to' percent by volume of a liquid, oil-soluble,water-insoluble corrosion inhibitor, from about 10 to 80 percent byvolume of a distilled petroleum fraction, from about 2 to 10 percent byvolume of a mutual solvent for water and said petroleum fraction, fromabout 2 to 10 percent by volume of a dispersing agent having the formulaROVV wherein R is a straight-chain hydrocarbon radical containing from12 to 20 carbon atoms, 0 is oxygen, and W is a polyoxyethylene chaincontaining between about 10 and 30 oxyethylene groups, and from O toabout 3 percent by volume of water.

References Cited in the file of this patent UNITED STATES PATENTS1,854,898 Gill et a1. Apr. 19, 1932 2,356,254 Lehmann et al Aug. 22,1944 2,649,415 Sundberg et al. Aug. 18, 1953 2,671,757 Wisherd Mar. 9,1954 UNITED STATES PATENT OFFICE CERTIFICATE SF CORRECTION Patent No.2,839,465 June 17, 1958 Loyd W, Jones It is herebj certified that errorappears in the-printed specification of the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 2, line 52, for "members" read numbers column 9, line 5'7 for "10to 30" read u 10 and 30 column 10, line 5, for "16 to 18" read 16 to 18carbon line 33, strike out "about"; line 48, for

"polyethylene" read polyoigrethylene line 64, for "10 to 30" read 10 and30 same line strike out "about" first occurrence Signed and sealed this9th day of September 1958.,

(SEAL) Attest:

KARL H. AXLINE ROBERT C. WATSON Attesting Officer Commissioner ofPatents UNITED STATES PATENT OFFlCE CERTIFICATE UP CORRECTION Patent Noa2,839,465 June 1'7, 1958 Loyd Wa Jones It is hereby certified that errorappears in thaprinted specification of the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 2, line 52, for "members" read me numbers column 9, line 5'7 for'10 to 30" read w 10 and 30 column 10 line 5, for "16 to 18" read M 16to 18 carbon m; line 33, strike out "about"; line 48, for polyethylene'"read m polyoxyethylene line 64 for "10 to 30" read 10 and 30 same line,strike out "about" first occurrence,

Signed and sealed this 9th day of September 19580 (SEAL) Attest:

KARL Hg. AXLINE ROBERT C. WATSON Attesting Ofiicer Commissioner ofPatents

1. A BRINE-DISPERSIBLE CORROSION-INHIBITING COMPOSITION COMPRISING FROMABOUT 10 TO 80 PERCENT BY VOLUME OF AN OIL-SOLUBLE, WATER-INSOLUBLECORROSION INHIBITOR, FROM ABOUT 10 TO 80 PERCENT BY VOLUME OF ADISTILLED PETROLEUM FRACTION, FROM ABOUT 2 TO 10 PERCENT BY VOLUMEPETROLEUM MUTUAL SOLVENT FOR WATER AND THE DISTILLED PETROLEUM FRACTION,AND FROM ABOUT 2 TO 10 PER CENT BY VOLUME OF A DISPERSING AGENT HAVINGTHE FORMULA ROW, WHEREIN R IS A NON-AROMATIC HYDROCARBON RADICALCONTAINING AT LEAST 12 CARBON ATOMS, O IS OXYGEN AND W IS A POLYGLYCOLCONTAINING AT LEAST 4 ETHER LINKAGES.